Jeff Wignall is a photographer and writer and the author of numerous books on photography, including The Joy of Digital Photography, The Kodak Guide to Shooting Great Travel Pictures, Kodak's Most Basic Book of 35mm Photography, and Winning Pictures. Check out Jeff's Photo Tip of the Day blog.

In one of the lessons for my online course “The Joy of Digital Photography,” I was trying to come up with a convincing anecdote about the value of photographing things when you see them — because you may never see them again. It’s a lesson most photographers have learned many times: If something of value places itself in front of your lens, you don’t have the luxury of being lazy: you must take the photograph.

The example I gave was of the “Old Stone Face” in New Hampshire and I think it’s a story worth sharing with everyone:

Sometimes a good photo opportunity has to almost whack you in the head to get your attention — and even then we think, “Oh, I’ll shoot that next time I see it.” But when it comes to taking pictures (like a lot of other things in life), sometimes we don’t get another chance, so it’s important to shoot it when you see it.

Several years ago, I was camping in New Hampshire and I stopped at the overlook to view the Old Man of the Mountain — a natural stone profile hundreds of feet high that is the symbol of New Hampshire. He’s even on the state license plate.

The “Great Stone Face” was the inspiration for a story by Nathaniel Hawthorne and had been looking down on Franconia Notch, New Hampshire, for an estimated 12,000 years. You would just assume he would be there for thousands more. And even though I’d shot him many times in the past, I decided to pause for an hour, haul my cameras out, and shoot more photos of him that day. It was hard to resist: The sky was blue, the lighting was nice, and his face made a good silhouette. I had other places I wanted to go, but I stopped and spent about an hour shooting him.

The next winter was a hard one in New England — colder than it had been for decades — and there was an unreal amount of snow and ice. One morning, to everyone’s horror and disbelief, a park ranger was driving by the mountain and noticed it: The Old Man was gone. Overcome by ice and winds, it simply crumbled and fell a thousand feet to the valley below. The face that we had come to depend on seeing for generations was just missing. Vanished. Everyone was shocked, and the governor, in his state of disbelief, talked of trying to devise a plan to resurrect the old man. But, of course, it was not to be.

I’m very sad the Old Man is gone, but I’m so happy I shot those photos. No photographer on earth will ever have the chance to shoot that “enduring” portrait again. His is a face lost to the ages, saved only by storytellers, poets and those photographers who bothered to take notice and make the effort to shoot it.

A few years prior to this my father had passed away and in the months after he died, I was going through a box of old photos and I came across a small print of him cooking dinner. It was just a snapshot — a throwaway almost — but I can’t tell you how much it meant to find that shot of him just doing something very ordinary — cooking dinner. Of course, he was the one that first took me to see the other “old man” in New Hampshire when I was a kid — and he was the one who taught me photography. The camera is an amazing time machine — it can bring us back to any moment in our lives if we make the effort to use it.

Take the picture when you see it. Things are not always as they are now.